Authorities have described the suspect as a black male, about 5 feet 7 inches tall, who was wearing jeans and a black-and-purple hooded sweatjacket. The man brandished a knife and made off with about $200 from the cash register, police said.

The store is located along the rotary where Springfield Street converges with Rimmon Avenue and Hamburg Street near the Chicopee city line. The suspect was last seen running toward Chicopee, police said.

There were no reported injuries. A 7-Eleven clerk reached this morning said he had no details about the incident.

Police are asking anyone with information to call detectives at (413) 787-6355.

The city line convenience store has been robbed in the past, including a 2008 gunpoint robbery that resulted in the arrest of three men.